The present invention seeks to improve communication across a network which includes mobile wireless network nodes, for example a mesh network. Such mobile wireless network nodes may be deployed as part of an ad hoc network required at short notice, for example, when emergency services attend an incident at which telecommunication facilities are required to be provided quickly on-site. (Such a mobile ad hoc network may sometimes be referred to as a MANET.) Hard-wired, mobile phone, 3G, 4G, and satellite communications systems are not always readily available or convenient to use and as such radio-based mobile wireless network access points may need to be rapidly deployed to provide an effective communications system on the ground. In certain circumstances, there may be movement of the network access points/nodes in the network. The ability to transmit data from one node to another may change rapidly according to local environmental conditions.
Commercially available routing algorithms typically choose a shortest or lowest cost path with no regard for the traffic that is being conveyed across it. Such algorithms are well suited to stable networks where links between nodes tend not to change significantly over time. Such algorithms can therefore afford to be rather time-consuming and network-resource intensive if such an investment of resources pays off with enhanced efficiency for the long-term. Such algorithms are however of little use when assessing the best route for data to be sent within a rapidly changing ad hoc network. Cisco Systems Inc for example have proposed the benefits of a policy governed network within a business's IT set-up, but in the context of allowing network managers the ability to manage the use of a network by different users and for various types of data and/or services in a manner that fits in with the objects of the business (see for example the “white paper” available at the following URL: www.cisco.com/en/US/prod/collateral/vpndevc/ps5712/ps11640/white_paper_c11-663616.pdf It is also known to provide layered mechanisms which prioritise data on a link-by-link basis (termed Per-Hop Behaviour), identify the data type according to the application that generated it, and allocate a Per-Hop Behaviour to the data.
U.S. 2011/0110309 discloses network node devices which cooperatively route traffic flow amongst wired and wireless networks by employing multi-path management processes. The possibility of a network device, programmed with a multi-path management software product, determining a particular path partly in dependence on the type of data is disclosed.
WO 2010/028311, relating to “enhanced wireless ad hoc communication techniques”, discloses the concept of generating a cost-based routing matrix for a network node which results in a routing table which takes account of traffic type, for example by means of weighting according to traffic type.
The patent publications mentioned above provide suggestions for sophisticated routing of traffic across networks including wireless nodes, including taking account of the type of data being transmitted, but would appear to represent overly complicated solutions that might be difficult to implement efficiently in practice, especially in the context of routing data efficiently in a fast changing wireless ad hoc network, where the conditions of the network may change so rapidly as to render such sophisticated systems of little practical use.
The present invention seeks to mitigate one or more of the above-mentioned problems. Alternatively or additionally, the present invention seeks to provide an improved method of routing traffic within a data network.